DATA PROTECTION REGISTRAR Elizabeth France has slapped an enforcement notice on British Gas subsidiary Centrica, ordering it to stop disclosing details to third parties of its massive customer database. The issue revolves around whether BG customers should be required to opt-in or opt-out of receiving information on third party products and services. BG's stance is that they should write to the company if they wish to opt-out; the registrar takes the opposite view. Centrica has 28 days to comply with the notice pending a Home Office tribunal this autumn. Ms France has also served notices on London Electricity and Southern Electric and is poised to issue four more to three electricity companies and a water company. Supermarket loyalty cards are also in her sights: 'If people choose to sell their privacy for Air Miles, that is their business', she says. 'But it's my business to ensure they know what they are doing.'